435 research outputs found
Opinions on rehabilitation care of young adults with transversal upper limb reduction deficiency in their transition to adulthood
PURPOSE: Young adults with transversal upper limb reduction deficiency experience limitations regarding education, employment and obtaining a driver's license. Contribution of rehabilitation care within these domains has been reported to be inadequate. This study evaluates the needs and suggestions of participants in rehabilitation care. METHODS: Two online focus groups with young adults and parents met during 4 consecutive days. Health care professionals joined a face-to-face focus group. Data analysis was based on framework analysis. RESULTS: The rehabilitation team was mainly consulted for problems with residual limb or for prostheses. Young adults and their parents were mostly unaware of resources regarding education, job selection or obtaining a driver's license. Professionals stated that these subjects were addressed during periodic appointments. Young adults didn't always attend these appointments due to limited perceived benefit. To improve rehabilitation care, participants suggested methods for providing relevant information, facilitating peer contact and offering dedicated training programs to practice work-related tasks, prepare for job interviews or enhance self-confidence. CONCLUSION: Periodic appointments do not fulfil needs of young adults with transversal upper limb reduction deficiency. To improve care, rehabilitation teams should offer age-relevant information, share peer stories, and create dedicated training programs
Discovery of Radio Outbursts in the Active Nucleus of M81
The low-luminosity active galactic nucleus of M81 has been monitored at
centimeter wavelengths since early 1993 as a by-product of radio programs to
study the radio emission from Supernova 1993J. The extensive data sets reveal
that the nucleus experienced several radio outbursts during the monitoring
period. At 2 and 3.6 cm, the main outburst occurred roughly in the beginning of
1993 September and lasted for approximately three months; at longer
wavelengths, the maximum flux density decreases, and the onset of the burst is
delayed. These characteristics qualitatively resemble the standard model for
adiabatically expanding radio sources, although certain discrepancies between
the observations and the theoretical predictions suggest that the model is too
simplistic. In addition to the large-amplitude, prolonged variations, we also
detected milder changes in the flux density at 3.6 cm and possibly at 6 cm on
short (less than 1 day) timescales. We discuss a possible association between
the radio activity and an optical flare observed during the period that the
nucleus was monitored at radio wavelengths.Comment: To appear in The Astronomical Journal. Latex, 18 pages including
embedded figures and table
Supporting Self-Regulated Learning in Online Learning Environments and MOOCs: A Systematic Review
Massive Open Online Courses (MOOCs) allow learning to take place anytime and anywhere with little external monitoring by teachers. Characteristically, highly diverse groups of learners enrolled in MOOCs are required to make decisions related to their own learning activities to achieve academic success. Therefore, it is considered important to support self-regulated learning (SRL) strategies and adapt to relevant human factors (e.g., gender, cognitive abilities, prior knowledge). SRL supports have been widely investigated in traditional classroom settings, but little is known about how SRL can be supported in MOOCs. Very few experimental studies have been conducted in MOOCs at present. To fill this gap, this paper presents a systematic review of studies on approaches to support SRL in multiple types of online learning environments and how they address human factors. The 35 studies reviewed show that human factors play an important role in the efficacy of SRL supports. Future studies can use learning analytics to understand learners at a fine-grained level to provide support that best fits individual learners. The objective of the paper is twofold: (a) to inform researchers, designers and teachers about the state of the art of SRL support in online learning environments and MOOCs; (b) to provide suggestions for adaptive self-regulated learning support.Teaching and Teacher Learning (ICLON
Immunopathology and Infectious Diseases Influenza A Virus (H5N1) Infection in Cats Causes Systemic Disease with Potential Novel Routes of Virus Spread within and between Hosts
The ongoing outbreak of avian influenza A virus (subtype H5N1) infection in Asia is of great concern because of the high human case fatality rate and the threat of a new influenza pandemic. Case reports in humans and felids suggest that this virus may have a different tissue tropism from other influenza viruses , which are normally restricted to the respiratory tract in mammals. To study its pathogenesis in a mammalian host , domestic cats were inoculated with H5N1 virus intratracheally (n ‫؍‬ 3) , by feeding on virus-infected chicks (n ‫؍‬ 3) , or by horizontal transmission (n ‫؍‬ 2) and examined by virological and pathological assays. In all cats , virus replicated not only in the respiratory tract but also in multiple extra-respiratory tissues. Virus antigen expression in these tissues was associated with severe necrosis and inflammation 7 days after inoculation. In cats fed on virus-infected chicks only , virus-associated ganglioneuritis also occurred in the submucosal and myenteric plexi of the small intestine , suggesting direct infection from the intestinal lumen. All cats excreted virus not only via the respiratory tract but also via the digestive tract. This study in cats demonstrates that H5N1 virus infection causes systemic disease and spreads by potentially novel routes within and between mammalian hosts. 4,5 The transmission of avian influenza A virus to mammalian species is of great concern because this may allow the virus to adapt to mammalian hosts and acquire pandemic potential. So far, however, there is only evidence for limited human spread. When bird-to-human transmission of H5N1 virus was first recorded in 1997, with 6 deaths of 18 hospitalized patients, 7-9 the question of why this virus was so pathogenic was raised. One hypothesis was that H5N1 virus had expanded its tissue tropism in humans beyond its normal location in the respiratory tract, resulting in systemic infection, 10 as is the usual situation in poultry infected with highly pathogenic avian influenza virus. 11 Although support for this hypothesis was provided neither by studies of patients who died in 1997 12 nor by experimental infections in cynomolgus macaques, Related to the question of tissue tropism is the question whether H5N1 virus can spread from one mammalian host to another and, if so, how. Although most human H5N1 virus infections have been due to contact with infected poultry or poultry products, probable person-toperson transmission has been recorded for two patients
Radio spectra and polarisation properties of a bright sample of Radio-Loud Broad Absorption Line Quasars
The origin of broad-absorption-line quasars (BAL QSOs) is still an open
issue. Accounting for ~20% of the QSO population, these objects present broad
absorption lines in their optical spectra generated from outflows with
velocities up to 0.2c. In this work we present the results of a multi-frequency
study of a well-defined radio-loud BAL QSO sample, and a comparison sample of
radio-loud non-BAL QSOs, both selected from the Sloan Digital Sky Survey
(SDSS).
We aim to test which of the currently-popular models for the BAL phenomenon -
`orientation' or 'evolutionary' - best accounts for the radio properties of BAL
quasars. Observations from 1.4 to 43 GHz have been obtained with the VLA and
Effelsberg telescopes, and data from 74 to 408 MHz have been compiled from the
literature.
The fractions of candidate GHz-peaked sources are similar in the two samples
(36\pm12% vs 23\pm8%), suggesting that BAL QSOs are not generally younger than
non-BAL QSOs. BAL and non-BAL QSOs show a large range of spectral indices,
consistent with a broad range of orientations. There is weak evidence (91%
confidence) that the spectral indices of the BAL QSOs are steeper than those of
non-BAL QSOs, mildly favouring edge-on orientations. At a higher level of
significance (\geq97%), the spectra of BAL QSOs are not flatter than those of
non-BAL QSOs, which suggests that a polar orientation is not preferred.Comment: Accepted by A&
Ebstein’s anomaly may be caused by mutations in the sarcomere protein gene MYH7
Ebstein's anomaly is a rare congenital heart malformation characterised by adherence of the septal and posterior leaflets of the tricuspid valve to the underlying myocardium. Associated abnormalities of left ventricular morphology and function including left ventricular noncompaction (LVNC) have been observed. An association between Ebstein's anomaly with LVNC and mutations in the sarcomeric protein gene MYH7, encoding β-myosin heavy chain, has been shown by recent studies. This might represent a specific subtype of Ebstein's anomaly with a Mendelian inheritance pattern. In this review we discuss the association of MYH7 mutations with Ebstein's anomaly and LVNC and its implications for the clinical care for patients and their family members.Congenital Heart Diseas
The theory of pulsar winds and nebulae
We review current theoretical ideas on pulsar winds and their surrounding
nebulae. Relativistic MHD models of the wind of the aligned rotator, and of the
striped wind, together with models of magnetic dissipation are discussed. It is
shown that the observational signature of this dissipation is likely to be
point-like, rather than extended, and that pulsed emission may be produced. The
possible pulse shapes and polarisation properties are described. Particle
acceleration at the termination shock of the wind is discussed, and it is
argued that two distinct mechanisms must be operating, with the first-order
Fermi mechanism producing the high-energy electrons (above 1 TeV) and either
magnetic annihilation or resonant absorption of ion cyclotron waves responsible
for the 100 MeV to 1 TeV electrons. Finally, MHD models of the morphology of
the nebula are discussed and compared with observation.Comment: 33 pages, to appear in Springer Lecture Notes on "Neutron stars and
pulsars, 40 years after the discovery", ed W.Becke
Natural enemies from South Africa for biological control of Lagarosiphon major (Ridl.) Moss ex Wager (Hydrocharitaceae) in Europe
The non-native invasive plant, Lagarosiphon major (Hydrocharitaceae) is a submersed aquatic macrophyte that poses a significant threat to water bodies in Europe. Dense infestations prove difficult to manage using traditional methods. In order to initiate a biocontrol programme, a survey for natural enemies of Lagarosiphon was conducted in South Africa. Several phytophagous species were recorded for the first time, with at least three showing notable promise as candidate agents. Amongst these, a leaf-mining fly, Hydrellia sp. (Ephydridae) that occurred over a wide distribution causes significant leaf damage despite high levels of parasitism by braconid wasps. Another yet unidentified fly was recorded mining the stem of L. major. Two leaf-feeding and shoot boring weevils, cf. Bagous sp. (Curculionidae) were recorded damaging the shoot tips and stunting the growth of the stem. Several leaf-feeding lepidopteran species (Nymphulinae) were frequently recorded, but are expected to feed on a wide range of plant species and are not considered for importation before other candidates are assessed. The discovery of several natural enemies in the country of origin improves the biological control prospects of L. major in Europe
Radio observations of ZwCl 2341.1+0000: a double radio relic cluster
Context: Hierarchal models of large scale structure (LSS) formation predict
that galaxy clusters grow via gravitational infall and mergers of (smaller)
mass concentrations, such as clusters and galaxy groups. Diffuse radio
emission, in the form of radio halos and relics, is found in clusters
undergoing a merger, indicating that shocks or turbulence associated with the
merger are capable of accelerating electrons to highly relativistic energies.
Here we report on radio observations of ZwCl 2341.1+0000, a complex merging
structure of galaxies located at z=0.27, using Giant Metrewave Radio Telescope
(GMRT) observations.
Aims: The main aim of the observations is to study the nature of the diffuse
radio emission in the galaxy cluster ZwCl 2341.1+0000.
Methods: We have carried out GMRT 610, 241, and 157 MHz continuum
observations of ZwCl 2341.1+0000. The radio observations are combined with
X-ray and optical data of the cluster.
Results: The GMRT observations show the presence of a double peripheral radio
relic in the cluster ZwCl 2341.1+0000. The spectral index is -0.49 \pm 0.18 for
the northern relic and -0.76 \pm 0.17 for the southern relic respectively. We
have derived values of 0.48-0.93 microGauss for the equipartition magnetic
field strength. The relics are probably associated with an outwards traveling
merger shock waves.Comment: 14 pages, 10 figures, accepted for publication in A&A on July 30,
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